Insights into the photovoltaic properties of indium sulfide as an electron transport material in perovskite solar cells

Ti-Doped AgNbO3 as Novel Dense Diffusion Barriers of Limiting Current Oxygen Sensors

The oxygen sensors with limiting current derived from a dense diffusion barrier have an excellent advantage of detecting oxygen partial pressure by controlling the ratio of air and fuel in combustion environments. Therefore, AgNb1-xTixO3-δ (wherein x varies from 0.1 to 0.3) was prepared as such a dense diffusion barrier layer for sensor application. Among the investigated compositions as a new condensed barrier for the diffusion of sensors, AgNb1-xTixO3-δ (x = 0.1, 0.2, 0.3) exhibits oxygen ionic conductivities from 1.37 × 10-4 to 5.78 × 10-3 S·cm-1 in the temperature range of 600-900 °C and outstanding stable electrochemical properties. Herein, we employ these novel materials as dense diffusion barriers and 8 mol % zirconia stabilized by yttria (8YSZ) as a solid-state electrolyte for the fabrication of the oxygen sensors with limiting current. We observed a direct connection between the limiting current and oxygen content within the interval of 0.5-5.0 mol % at 800 °C and a low working voltage. The increase of Ti-doping amount in AgNbO3 accelerates the sensing response to oxygen gas and promotes the service life of the sensor.

Improved eco-friendly CsSn0.5Ge0.5I3 perovskite photovoltaic efficiency beyond 20% with SMe-TATPyr hole-transporting layer

Perovskites composed of inorganic cesium (Cs) halide provide a route to thermally resistant solar cells. Nevertheless, the use of hole-transporting layers (HTLs) with hydrophobic additives is constrained by moisture-induced phase deterioration. Due to significant electrical loss, dopant-free HTLs are unable to produce practical solar cells. In this article, we designed a two-dimensional 1,3,6,8-tetrakis[5-(N,N-di(p-(methylthio)phenyl)amino-p-phenyl)-thiophen-2-yl]pyrene (termed SMe-TATPyr) molecule as a new HTL to regulate electrical loss in lead-free perovskite solar cells (PSCs). We optimized the power conversion efficiency (PCE) of PSCs based on mixed tin (Sn)/germanium (Ge) halide perovskite (CsSn0.5Ge0.5I3) by exploring different factors, such as the deep and shallow levels of defects, density of states at the valence band (NV), thickness of the perovskite film, p-type doping concentration (NA) of HTL, the series and shunt resistances, and so on. We carried out comparative research by employing the 1D-SCAPS (a solar cell capacitance simulator) analysis tool. Through optimization of the PSC, we obtained the highest parameters in the simulated solar cell structure of fluorine tin oxide (FTO)/titanium dioxide (TiO2)/CsSn0.5Ge0.5I3/SMe-TATPyr/gold (Au), and the PCE reached up to 20% with a fill factor (FF) of 81.89%.

Comparative study of distinct halide composites for highly efficient perovskite solar cells using a SCAPS-1D simulator

This research investigates the influence of halide-based methylammonium-based perovskites as the active absorber layer (PAL) in perovskite solar cells (PSCs). Using SCAPS-1D simulation software, the study optimizes PSC performance by analyzing PAL thickness, temperature, and defect density impact on output parameters. PAL thickness analysis reveals that increasing thickness enhances JSC for MAPbI3 and MAPbI2Br, while that of MAPbBr3 remains steady. VOC remains constant, and FF and PCE vary with thickness. MAPbI2Br exhibits the highest efficiency of 22.05% at 1.2 μm thickness. Temperature impact analysis shows JSC, VOC, FF, and PCE decrease with rising temperature. MAPbI2Br-based PSC achieves the highest efficiency of 22.05% at 300 K. Contour plots demonstrate that optimal PAL thickness for the MAPbI2Br-based PSC is 1.2 μm with a defect density of 1 × 1013 cm-3, resulting in a PCE of approximately 22.05%. Impedance analysis shows the MAPbBr3-based PSC has the highest impedance, followed by Cl2Br-based and I-based perovskite materials. A comparison of QE and J-V characteristics indicates MAPbI2Br offers the best combination of VOC and JSC, resulting in superior efficiency. Overall, this study enhances PSC performance with MAPbI2Br-based devices, achieving an improved power conversion efficiency of 22.05%. These findings contribute to developing more efficient perovskite solar cells using distinct halide-based perovskite materials.

Achieving above 24% efficiency with non-toxic CsSnI3 perovskite solar cells by harnessing the potential of the absorber and charge transport layers

Lead toxicity is a barrier to the widespread commercial manufacture of lead halide perovskites and their use in solar photovoltaic (PV) devices. Eco-friendly lead-free perovskite solar cells (PSCs) have been developed using certain unique non- or low-toxic perovskite materials. In this context, Sn-based perovskites have been identified as promising substitutes for Pb-based perovskites due to their similar characteristics. However, Sn-based perovskites suffer from chemical instability, which affects their performance in PSCs. This study employs theoretical simulations to identify ways to improve the efficiency of Sn-based PSCs. The simulations were conducted using the SCAPS-1D software, and a lead-free, non-toxic, and inorganic perovskite absorber layer (PAL), i.e. CsSnI3 was used in the PSC design. The properties of the hole transport layer (HTL) and electron transport layer (ETL) were tuned to optimize the performance of the device. Apart from this, seven different combinations of HTLs were studied, and the best-performing combination was found to be ITO/PCBM/CsSnI3/CFTS/Se, which achieved a power conversion efficiency (PCE) of 24.73%, an open-circuit voltage (VOC) of 0.872 V, a short-circuit current density (JSC) of 33.99 mA cm-2 and a fill factor (FF) of 83.46%. The second highest PCE of 18.41% was achieved by the ITO/PCBM/CsSnI3/CuSCN/Se structure. In addition to optimizing the structure of the PSC, this study also analyzes the current density-voltage (J-V) along with quantum efficiency (QE), as well as the impact of series resistance, shunt resistance, and working temperature, on PV performance. The results demonstrate the potential of the optimized structure identified in this study to enhance the standard PCE of PSCs. Overall, this study provides important insights into the development of lead-free absorber materials and highlights the potential of using CsSnI3 as the PAL in PSCs. The optimized structure identified in this study can be used as a base for further research to improve the efficiency of Sn-based PSCs.

Harnessing the potential of CsPbBr3-based perovskite solar cells using efficient charge transport materials and global optimization

Perovskite solar cells (PSCs) have become a possible alternative to traditional photovoltaic devices for their high performance, low cost, and ease of fabrication. Here in this study, the SCAPS-1D simulator numerically simulates and optimizes CsPbBr3-based PSCs under the optimum illumination situation. We explore the impact of different back metal contacts (BMCs), including Cu, Ag, Fe, C, Au, W, Pt, Se, Ni, and Pd combined with the TiO2 electron transport layer (ETL) and CFTS hole transport layer (HTL), on the performance of the devices. After optimization, the ITO/TiO2/CsPbBr3/CFTS/Ni structure showed a maximum power conversion efficiency (PCE or η) of 13.86%, with Ni as a more cost-effective alternative to Au. After the optimization of the BMC the rest of the investigation is conducted both with and without HTL mode. We investigate the impact of changing the thickness and the comparison with acceptor and defect densities (with and without HTL) of the CsPbBr3 perovskite absorber layer on the PSC performance. Finally, we optimized the thickness, charge carrier densities, and defect densities of the absorber, ETL, and HTL, along with the interfacial defect densities at HTL/absorber and absorber/ETL interfaces to improve the PCE of the device; and the effect of variation of these parameters is also investigated both with and without HTL connected. The final optimized configuration achieved a VOC of 0.87 V, JSC of 27.57 mA cm-2, FF of 85.93%, and PCE of 20.73%. To further investigate the performance of the optimized device, we explore the impact of the temperature, shunt resistance, series resistance, capacitance, generation rate, recombination rate, Mott-Schottky, JV, and QE features of both with and without HTL connected. The optimized device offers the best thermal stability at a temperature of 300 K. Our study highlights the potential of CsPbBr3-based PSCs and provides valuable insights for their optimization and future development.